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A368250
Decimal expansion of Sum_{k>=2} (zeta(k)/zeta(2*k) - 1).
6
8, 4, 8, 6, 3, 3, 8, 6, 7, 9, 6, 4, 8, 8, 3, 6, 3, 2, 6, 8, 4, 9, 0, 0, 1, 2, 0, 9, 0, 4, 3, 0, 4, 6, 2, 9, 6, 0, 0, 1, 6, 6, 4, 4, 6, 8, 8, 1, 7, 5, 5, 1, 7, 1, 6, 7, 9, 6, 2, 0, 3, 0, 9, 0, 0, 3, 6, 5, 4, 2, 2, 1, 3, 7, 1, 3, 0, 2, 1, 2, 9, 1, 8, 8, 6, 6, 3, 4, 8, 1, 0, 1, 1, 5, 3, 7, 0, 2, 0, 6, 3, 4, 4, 3, 7
OFFSET
0,1
LINKS
FORMULA
Equals Sum_{k>=2} mu(k)^2/(k*(k-1)) = Sum_{k>=2} 1/A368249(k).
Equals Sum_{k>=1} 1/A072777(k).
Equals lim_{m->oo} (1/m) * Sum_{k=1..m} A368251(k).
EXAMPLE
0.84863386796488363268490012090430462960016644688175...
MAPLE
evalf(sum(Zeta(k)/Zeta(2*k) - 1, k = 2 .. infinity), 120);
PROG
(PARI) sumpos(k=2, zeta(k)/zeta(2*k) - 1)
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Amiram Eldar, Dec 19 2023
STATUS
approved